Undergraduate student studies vasculature development in mice

Biology student Tanner Hoog was recently awarded a grant for his research into the vasculature development of mouse embryos. Hoog is working in the lab of Dr. Ryan Udan, assistant professor of biology at Missouri State.

“It has been shown that the vasculature of a developing mouse embryo requires proper hemodynamic loading—the force that the blood serum exerts onto the vessel walls—to induce a blood vessel hierarchy with larger, more structurally defined vessels being closer to the heart, and smaller, more capillary-like vessels growing in the periphery,” said Hoog. “My research focuses on taking these concepts previously shown to play a role in vasculature development and see how it applies to heart development.”

Discovering alterations

In order to achieve this goal, Hoog dissects the embryos and injects them with different types of chemicals to alter the hemodynamic load and then views the altered hearts using an advanced form of 3D microscopy.

“To create an environment of ‘low flow’ within the vasculature, we inject the embryonic yolk sac with a polymerizing agent which prevents red blood cells from entering circulation and thus creates less pressure within the vasculature,” said Hoog. “To induce a ‘high flow’ condition within the circulatory system, we inject the vessels directly with the chemical hetastarch. This viscous addition to the vessels increases the overall hemodynamic load.”

After a 24-hour culturing period during which the embryonic heart continuously pumps the altered blood, the heart is then imaged using an optimal projection tomography, or OPT, microscope.

“What makes the OPT so unique is its ability to generate high resolution 3D images and even display internal structures with clarity,” said Hoog. “Our embryos are stained with a fluorescent antibody that selectively attaches to the embryonic heart. This allows us to visualize the structure of the heart with high clarity and see precisely how the heart is changing when exposed to the afore mentioned treatment types.”

Helping humans

After spending summer 2016 working with the OPT microscope at the Baylor College of Medicine, Hoog now has to process all the images of embryos accumulated over the semester. He believes this research is important for one critical reason.

“There are a large percentage of babies born each year with congenital heart defects, or CHDs,” said Hoog. “These defects include anything that alters the development of the heart and impairs the heart’s functionality. While having a congenital heart defect is not a death sentence, we still don’t understand the mechanisms behind what causes them in the first place. Our goal is to understand how CHDs arise so that they can be treated or prevented from ever forming.”

The grant money that Hoog received from the Tri-Beta Honor Society will be used for the next step in his research, which involves looking at the altered heart structure on a cellular—and potentially genetic—level. Hoog looks forward to continuing his research while in the accelerated master’s program and graduating in Spring 2017 when he will then become a graduate student.

“I know I want to continue studying developmental biology, so the next step in the road for me is to start applying to PhD programs,” said Hoog. “It is not enough for me to simply study a concept; I want to be able to distribute the knowledge. I very much so want to live in a world where knowledge is not only embraced, but also understood. These are the values that I hold close to me and inspire me to obtain a doctorate. It is not about making me a better a person intellectually—it is about making the world a better place.”